Received power estimation device, received power estimation method, and program

Abstract

This received signal power estimation device comprises an evaluation area division unit, a matching data generation unit, and a received signal power calculation unit. The evaluation area division unit carries out a process for dividing an evaluation area which is a geographic area for which the received signal power is to be evaluated into a received signal power evaluation mesh, and a process for creating, for the evaluation area, a parameter evaluation mesh for calculating the value of a radio wave propagation calculation parameter which is used to calculate the received signal power at an evaluation point. The matching data generation unit generates data which indicates a correspondence between the received signal power evaluation mesh and the parameter evaluation mesh. The received signal power calculation unit calculates a received signal power at an evaluation point by means of the radio wave propagation calculation which uses the value of the radio wave propagation calculation parameter based on topography or geographic feature information included in the parameter evaluation mesh corresponding to the received signal power evaluation mesh to which the evaluation point belongs.

Description

[Technical Field]

[0001] The present invention relates to a received power estimation device, a received power estimation method, and a program. [Background technology]

[0002] As wireless use advances, in addition to public wireless systems operated by carriers, the use of private wireless systems, which allow users to build their own wireless systems, is expanding. In addition to Wi-Fi, which can be used without a radio wave license, new wireless systems such as local 5G, which require a radio wave license to operate and are not affected by interference when using the wireless system, are expected to become more widely used.

[0003] When using such wireless systems that require a radio wave license, it is necessary to conduct an interference assessment and prove that there will be no impact on existing users due to interference. For example, in the case of local 5G, the Ministry of Internal Affairs and Communications' directive (Reference 1: Internet<https: / / www.soumu.go.jp / main_content / 000711787.pdf> ) has established radio wave propagation calculation formulas for interference evaluation.<https: / / 5gmf.jp / > )'s "Local 5G License Application Support Manual" (Reference 2: Internet<https: / / 5gmf.jp / case / 4484 / > ) provides specific methods for plotting radio wave propagation calculation results when evaluating interference.

[0004] Conventionally, the received power level has been evaluated by dividing a map into meshes and calculating the received power at each received power evaluation point (hereinafter also referred to as evaluation point) determined by a predetermined method either at the center of the mesh or within the mesh (see, for example, Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 4-100415 [Patent Document 2] Japanese Patent Application Publication No. 4-100417 Summary of the Invention [Problem to be solved by the invention]

[0006] In conventional technology, the mesh size used to evaluate the received power level is the same as the mesh size used to calculate the parameter values ​​used in radio wave propagation calculations. However, how to define the area used to derive parameter values ​​that vary due to the influence of terrain and objects in a radio wave propagation calculation model depends on the individual radio wave propagation calculation model. For example, consider the case where ITU-R P.1411 is applied to a radio wave propagation calculation model. The radio wave propagation calculation model in ITU-R P.1411 uses average road width and average building height as parameters. Suppose the mesh size used to evaluate the received power level is 10 meters per side, and the received power is calculated for each mesh. In this case, there is a possibility that roads, buildings, etc., which are the basis for calculating the parameter values, do not exist in meshes of this size, so it may be impossible to calculate the average road width and average building height. For meshes for which the average road width and average building height cannot be obtained, the received power cannot be calculated.

[0007] In view of the above circumstances, the present invention aims to provide a received power estimation device, a received power estimation method, and a program that can calculate estimated received power regardless of the size of a mesh that is the unit for evaluating received power. [Means for solving the problem]

[0008] A received power estimation device of one embodiment of the present invention comprises an evaluation range division unit that performs the process of dividing an evaluation range, which is a geographical range in which received power is evaluated, into received power evaluation meshes for calculating received power at evaluation points located within the evaluation range, and the process of creating a parameter evaluation mesh in the evaluation range for obtaining values ​​of radio wave propagation calculation parameters used in calculating the received power at the evaluation points; a matching data generation unit that generates data indicating the correspondence between the received power evaluation meshes and the parameter evaluation meshes; and a received power calculation unit that calculates the received power at the evaluation points by radio wave propagation calculation using values ​​of the radio wave propagation calculation parameters obtained based on information on topography or features included in the parameter evaluation mesh that corresponds to the received power evaluation mesh to which the evaluation points belong.

[0009] A received power estimation method according to one aspect of the present invention includes a mesh division step of dividing an evaluation range, which is a geographical range in which received power is evaluated, into received power evaluation meshes for calculating received power at evaluation points located within the evaluation range; a mesh creation step of creating a parameter evaluation mesh in the evaluation range for obtaining values ​​of radio wave propagation calculation parameters used in calculating received power at the evaluation points; a matching data generation step of generating data indicating a correspondence between the received power evaluation meshes and the parameter evaluation meshes; and a received power calculation step of calculating received power at the evaluation points by radio wave propagation calculation using values ​​of the radio wave propagation calculation parameters obtained based on information on topography or features included in the parameter evaluation mesh that corresponds to the received power evaluation mesh to which the evaluation points belong.

[0010] One aspect of the present invention is a program for causing a computer to function as the above-described received power estimation device. [Effects of the Invention]

[0011] According to the present invention, it is possible to calculate an estimated received power regardless of the size of the mesh that is the unit for evaluating the received power. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a functional block diagram showing the configuration of a received power estimation device according to an embodiment of the present invention. [Figure 2] 10 is a diagram showing the correspondence between a reception power evaluation mesh and an evaluation point side parameter evaluation mesh according to the embodiment. FIG. [Figure 3] FIG. 10 is a diagram showing an example of a match list according to the embodiment. [Figure 4] FIG. 4 is a flowchart showing the processing of the received power estimation device according to the embodiment. [Figure 5] FIG. 10 is a diagram showing an example of creating a base station side parameter evaluation mesh according to the embodiment. [Figure 6] 10A and 10B are diagrams showing an example of creating an evaluation point side parameter evaluation mesh according to the embodiment. [Figure 7] FIG. 2 is a diagram illustrating an example of a hardware configuration of a received power estimation device according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] An embodiment of the present invention will be described in detail below with reference to the drawings. A received power estimation device of this embodiment individually derives the mesh size, which is a unit of geographical area for evaluating received power at received power evaluation points, and the mesh size for calculating values ​​of radio wave propagation calculation parameters. Furthermore, the received power estimation device of this embodiment determines the mesh size for calculating values ​​of radio wave propagation calculation parameters by defining and judging a threshold value for the autocorrelation coefficient of fluctuations in the calculated received power according to the frequency or the radio wave propagation calculation model used to calculate the received power. This makes it possible to derive parameter values ​​in units of meshes of a size appropriate for calculating radio wave propagation calculation parameters, regardless of the mesh size for evaluating received power.

[0014] FIG. 1 is a functional block diagram showing the configuration of a received power estimation device 1 according to an embodiment of the present invention. The received power estimation device 1 can be realized by, for example, a computer device. FIG. 1 shows only the functional blocks related to this embodiment. The received power estimation device 1 includes a wireless system information input unit 11, a base station information input unit 12, an evaluation range designation unit 13, a map database (DB) 14, an evaluation range division unit 15, a base station side parameter calculation unit 16, an evaluation point side parameter calculation unit 17, a matching list generation unit 18, a received power calculation unit 19, and an evaluation result output unit 20.

[0015] The wireless system information input unit 11, base station information input unit 12, and evaluation range designation unit 13 are input units for inputting conditions that are prerequisites for calculating the received power of radio waves emitted from a base station. The input units receive information entered by a user using, for example, a keyboard, a mouse, a touch panel, buttons, or keys. Alternatively, the input unit may receive information from another computer device connected via a network or read information from a computer-readable recording medium.

[0016] The wireless system information input unit 11 inputs information about the wireless system such as the effective radiated power of the wireless system, the antenna pattern, etc. As the effective radiated power, the transmission power, the antenna gain, the feeder loss, etc. may be input.

[0017] The base station information input unit 12 inputs base station information. The base station information includes information related to the base station, such as the installation location, installation environment, and installation information of the base station. As the installation location, latitude, longitude, height, etc. may be input. Height may be height above ground or altitude. Furthermore, indoor or outdoor, etc. is input as the installation environment, and in the case of indoors, building entry loss, etc. are further input. As the installation method, the north-south, east-west, and elevation angles of the antennas of the base station, etc. are input.

[0018] The evaluation range designation unit 13 designates an evaluation range on the map in accordance with the operator's operation or other conditions.

[0019] The map DB 14 is a storage unit that stores map data. The map data includes information such as topographical information, building information, structure information, and land use information. Topographical information is information such as latitude, longitude, and altitude. Building information, structure information, and land use information are linked to topographical information. Building information and structure information are information on land features. Building information is information such as the outline and height of a building. Structure information is information such as the location and width of a road. Land use information is information such as building land, sea level, lake surface, farmland, and forest.

[0020] The evaluation range dividing unit 15 has a function of dividing the geographical evaluation range specified by the evaluation range specifying unit 13 to create a received power evaluation mesh, a base station side parameter evaluation mesh, and an evaluation point side parameter evaluation mesh. The evaluation range dividing unit 15 has a received power evaluation mesh creating unit 151, a radio wave propagation calculation model selecting unit 152, a base station side parameter evaluation mesh creating unit 153, and an evaluation point side parameter evaluation mesh creating unit 154.

[0021] The received power evaluation mesh creation unit 151 has a function of creating a received power evaluation mesh by dividing the evaluation range according to input by an operator or other conditions. The received power evaluation mesh is a unit for evaluating the received power at the received power evaluation point. The radio wave propagation calculation model selection unit 152 has a function of selecting a radio wave propagation calculation model to be used for calculating the received power at the received power evaluation point. For example, the received power level is calculated using the radio wave propagation calculation model.

[0022] The base station side parameter evaluation mesh creation unit 153 has a function of creating a base station side parameter evaluation mesh for the vicinity of the base station in the evaluation range when the radio wave propagation calculation model includes base station side parameters. The base station side parameter evaluation mesh is an area for calculating the values ​​of the base station side parameters. The base station side parameters are parameters for radio wave propagation calculation whose values ​​vary depending on information about the vicinity of the base station.

[0023] The evaluation point side parameter evaluation mesh creation unit 154 has a function of dividing the evaluation range and creating an evaluation point side parameter evaluation mesh when an evaluation point side parameter is included in the radio wave propagation calculation model. The evaluation point side parameter evaluation mesh is an area for calculating the value of the evaluation point side parameter. The evaluation point side parameter is a parameter for radio wave propagation calculation whose value varies depending on information around the received power evaluation point.

[0024] The base station side parameter calculation unit 16 has a function of deriving the values ​​of the base station side parameters. That is, the base station side parameter calculation unit 16 determines whether or not there are base station side parameters that need to be calculated based on map data, such as information on topography and features, among the base station side parameters used in the radio wave propagation calculation model. If the base station side parameter calculation unit 16 determines that there are such base station side parameters, it acquires information for calculating the values ​​of the base station side parameters from the map DB 14, based on the base station side parameter evaluation mesh created by the base station side parameter evaluation mesh creation unit 153. The base station side parameter calculation unit 16 derives the values ​​of the base station side parameters using the acquired information. Information that is not acquired from the map DB 14, such as base station information, may also be used to derive the values ​​of the base station side parameters.

[0025] The evaluation point side parameter calculation unit 17 has a function of deriving the values ​​of the evaluation point side parameters. That is, the evaluation point side parameter calculation unit 17 determines whether or not there are evaluation point side parameters that need to be calculated based on map data such as information on topography and features among the evaluation point side parameters used in the radio wave propagation calculation model. If the evaluation point side parameter calculation unit 17 determines that there are such evaluation point side parameters, it acquires information for calculating the values ​​of the evaluation point side parameters from the map DB 14 based on the evaluation point side parameter evaluation mesh created by the evaluation point side parameter evaluation mesh creation unit 154. The evaluation point side parameter calculation unit 17 derives the values ​​of the evaluation point side parameters using the acquired information. Information that is not acquired from the map DB 14 may also be used to derive the values ​​of the evaluation point side parameters.

[0026] The matching list generation unit 18 has a function of creating a matching list that matches the received power evaluation mesh, the base station side parameter evaluation mesh, and the evaluation point side parameter evaluation mesh created by the evaluation range division unit 15. The matching list generation unit 18 further stores the values ​​of the base station side parameters and evaluation point side parameters used in the radio wave propagation calculation model in the matching list.

[0027] The received power calculation unit 19 has a function of calculating the received power for each received power evaluation point in accordance with a radio wave propagation calculation model using at least a portion of the wireless system information, base station information, base station parameters, and evaluation point parameters. The evaluation result output unit 20 has a function of outputting the calculation results of the received power calculation unit 19 using any output method. For example, the evaluation result output unit 20 may display the received power in each received power evaluation mesh on a map using a GUI (Graphical User Interface) or may output it as text information.

[0028] FIG. 2 is a diagram showing a received power evaluation mesh M1 and an evaluation point side parameter evaluation mesh M2. FIG. 2 shows an example in which the size of the received power evaluation mesh M1 and the size of the evaluation point side parameter evaluation mesh M2 are different. In this example, the size of the received power evaluation mesh M1 is 20 [m] × 20 [m]. On the other hand, the size of the evaluation point side parameter evaluation mesh M2 is 100 [m] × 100 [m]. Note that the base station side parameter evaluation mesh is created around each base station within the evaluation range. The size of the base station side parameter evaluation mesh may be larger, smaller, or the same as the size of the evaluation point side parameter evaluation mesh M2.

[0029] FIG. 3 is a diagram showing an example of a matching list. The matching list is data that associates a base station side parameter evaluation mesh, a base station side parameter value obtained from the base station side parameter evaluation mesh, an evaluation point side parameter evaluation mesh, an evaluation point side parameter value obtained from the evaluation point side parameter evaluation mesh, and a received power evaluation point. The base station side parameter evaluation mesh is represented by identification information of the base station side parameter evaluation mesh, and the evaluation point side parameter evaluation mesh is represented by identification information of the evaluation point side parameter evaluation mesh. A received power evaluation point belongs to one of the received power evaluation meshes. Therefore, the matching list shows the association between the base station side parameter evaluation mesh, the evaluation point side parameter evaluation mesh, and the received power evaluation mesh to which the received power evaluation point belongs. The matching list shown in FIG. 3 includes one base station side parameter value and one evaluation point side parameter value, but there may be multiple base station side parameters and multiple evaluation point side parameters.

[0030] 4 is a flow diagram showing the processing of the received power estimation device 1. First, an operator or another person inputs wireless system information such as the effective radiated power and antenna pattern of the wireless system through the wireless system information input unit 11 (step S1). Next, the operator or another person inputs base station information including the base station installation location and various setting values ​​used to calculate the received power level through the base station information input unit 12 (step S2). Note that the order of input in steps S1 and S2 may be reversed.

[0031] Next, the operator or others inputs the selection of the evaluation range using the evaluation range designation unit 13 (step S3). For example, the operator may select the evaluation range by designating the evaluation range on a GUI such as a map displayed on a display provided in the received power estimation device 1, by inputting information such as the latitude and longitude of the evaluation range in text, or by combining these selection methods.

[0032] Next, the reception power evaluation mesh creation unit 151 divides the evaluation range selected in step S3 into reception power evaluation meshes (step S4). For example, the division of the reception power evaluation mesh may be specified by the number of meshes, may be specified by the mesh size, or may be specified by a combination of these specifying methods. Furthermore, the specification of the division of the reception power evaluation mesh may be input by the evaluation range specification unit 13, or may be stored in advance in the evaluation range division unit 15.

[0033] Next, the radio wave propagation calculation model selection unit 152 selects a radio wave propagation calculation method (step S5). The radio wave propagation calculation model selection unit 152 may select one radio wave propagation calculation model as the radio wave propagation calculation method, or may select a calculation method that combines multiple radio wave propagation calculation models depending on the distance between the base station and the received power evaluation point or other conditions. For example, the radio wave propagation calculation model selection unit 152 selects a radio wave propagation calculation model depending on information such as frequency included in the input wireless system information, whether the received power evaluation point is indoors or outdoors, whether there is line of sight between the base station and the received power evaluation point, etc. The radio wave propagation calculation model is selected for each combination of an evaluation point or a received power evaluation mesh and a base station or a base station side parameter evaluation mesh, for example.

[0034] For reference, the radio wave propagation calculation models described in the "Local 5G License Application Support Manual" (Reference 2) of the 5th Generation Mobile Communications Promotion Forum (5GMF) are discussed below, with a section on "Outdoors with no line of sight" that is part of ITU-R P.1411 for the 28 GHz band. As will be discussed later, even in the case of local 5G systems, there are cases where one radio wave propagation calculation model is selected or where multiple radio wave propagation models are combined for evaluation depending on the frequency and the environment, such as whether it is indoors or outdoors or whether there is line of sight.

[0035] After selecting the radio wave propagation calculation method, the evaluation range division unit 15 performs processing to derive parameter values ​​according to the selected calculation method. First, the base station side parameter evaluation mesh creation unit 153 determines whether the base station side parameters are used in the calculation method selected in step S5 (step S6).

[0036] If the base station side parameter evaluation mesh creation unit 153 determines in step S6 that the base station side parameters will be used (step S6: YES), it performs the process of step S7. That is, the base station side parameter evaluation mesh creation unit 153 creates a base station side parameter evaluation mesh for deriving the value of the base station side parameter in the evaluation range selected in step S3 (step S7). For each base station side parameter evaluation mesh created in step S7, the base station side parameter calculation unit 16 reads out map data of the area corresponding to the base station side parameter evaluation mesh from the map DB 14, and calculates the value of the base station side parameter using information included in the read map data (step S8).

[0037] On the other hand, if the base station side parameter evaluation mesh creation unit 153 determines in step S6 that the base station side parameters will not be used (step S6: NO), or after the processing of step S8, the received power estimation device 1 performs the processing of step S9. That is, the evaluation point side parameter evaluation mesh creation unit 154 determines whether or not the evaluation point side parameters will be used in the calculation method selected in step S5 (step S9).

[0038] If the evaluation point side parameter evaluation mesh creation unit 154 determines in step S9 that the evaluation point side parameters will be used (step S9: YES), it performs the process of step S10. That is, the evaluation point side parameter evaluation mesh creation unit 154 divides the evaluation range selected in step S3 into evaluation point side parameter evaluation meshes for deriving the values ​​of the evaluation point side parameters (step S10). For each evaluation point side parameter evaluation mesh divided in step S10, the evaluation point side parameter calculation unit 17 reads out map data of the area corresponding to the evaluation point side parameter evaluation mesh from the map DB 14, and calculates the values ​​of the evaluation point side parameters using information included in the read map data (step S11).

[0039] The matching list generation unit 18 generates a matching list (step S12). The matching list is data that associates the received power evaluation mesh divided in step S4, the base station side parameter evaluation mesh divided in step S7, the base station side parameter values ​​calculated for the base station side parameter evaluation mesh in step S8, the evaluation point side parameter evaluation mesh divided in step S9, and the evaluation point side parameter values ​​calculated for the evaluation point side parameter evaluation mesh in step S10. In the case of the matching list shown in Fig. 3, the received power evaluation points belonging to the received power evaluation mesh are set as the information on the received power evaluation mesh.

[0040] If the evaluation point side parameter evaluation mesh creation unit 154 determines in step S9 that the evaluation point side parameters will not be used (step S9: NO), or after the processing of step S12, the received power calculation unit 19 performs the processing of step S13. That is, the received power calculation unit 19 calculates the received power for each received power evaluation point using the radio wave propagation calculation method selected in step S5 (step S13). If a matching list has been generated, the received power calculation unit 19 reads out from the matching list the values ​​of the base station side parameters calculated for the base station side parameter evaluation mesh associated with the received power evaluation mesh to which the received power evaluation point belongs, and the values ​​of the evaluation point side parameters calculated for the evaluation point side parameter evaluation mesh associated with the received power evaluation mesh to which the received power evaluation point belongs. The received power calculation unit 19 calculates the received power level at the received power evaluation point by using the read values ​​of the base station side parameters and the values ​​of the evaluation point side parameters in the radio wave propagation calculation method selected in step S5 for the received power evaluation point or the received power evaluation mesh to which the received power evaluation point belongs. If there are multiple base stations, the received power level is calculated for each combination of the received power evaluation point and the base station. The evaluation result output unit 20 outputs the evaluation result indicating the received power level for each received power evaluation point calculated in step S13 (step S14).

[0041] The size at which the base station side parameter evaluation mesh and the evaluation point side parameter evaluation mesh should be created depends on the radio wave propagation calculation model and frequency. These parameters are modeled taking into account the influence of topography and other features. Therefore, it is necessary to consider the correlation between the representative point and other points in the mesh in the calculation of the radio wave propagation calculation model used. Note that the representative point is the installation position of the base station in the case of the base station side, and is, for example, the center point of the evaluation point side parameter evaluation mesh in the case of the received power evaluation point side.

[0042] The details of an example of applying base station parameters and evaluation point parameters to the radio wave propagation calculation method are explained based on an actual radio wave propagation calculation model. Here, we explain the radio wave propagation model of ITU-R P.1411 described in the Local 5G License Application Support Manual. The received power Pr is calculated using the following formula (1).

[0043]

number

[0044] The propagation loss amount L in the case of line of sight outdoors is calculated by the following formula (2).

[0045]

number

[0046] d in the above formula (2) RD is calculated using the following formula (3):

[0047]

number

[0048] d RD The value of is calculated by inputting a value between 0 and 4 into k in the following equation (4). k The value of is calculated by inputting the value into the above formula (3).

[0049]

number

[0050] Also, L in equation (2) dRD The value is calculated using the following formula (5).

[0051]

number

[0052] Also, L dRD The value of is calculated by inputting a value from 0 to 4 into k in the following equation (6) and calculating all L dk After determining the value of (1), the value within the range of the conditions of the above formula (5) is input and calculated.

[0053]

number

[0054] In the above formula, the average building height h r is the average height of buildings around the base station. That is, the average building height h r is a base station parameter. Fig. 5 is a diagram showing an example of creating a base station parameter evaluation mesh when finding the average building height around a base station. In Fig. 5, the base station parameter evaluation mesh creation unit 153 creates base station parameter evaluation meshes M3 and M4 by using squares of a predetermined size centered on the positions of two base stations B1 and B2. The base station parameter calculation unit 16 reads out map data of the area corresponding to the base station parameter evaluation mesh from the map DB 14. The base station parameter calculation unit 16 calculates the average building height h based on the height of each building indicated by the building information included in the read map data. r Calculate.

[0055] Similarly, in the above equation, the road width w is the average value of the road widths around the reception power evaluation point. In other words, the road width w is an evaluation point-side parameter. FIG. 6 is a diagram showing an example of creating an evaluation point-side parameter evaluation mesh when calculating the average road width around the reception power evaluation point. In FIG. 6, the evaluation point-side parameter evaluation mesh creation unit 154 divides the evaluation range M5 into square meshes of a predetermined size to create an evaluation point-side parameter evaluation mesh M6. The evaluation point-side parameter calculation unit 17 reads out map data of the area corresponding to the evaluation point-side parameter evaluation mesh M6 from the map DB 14. The evaluation point-side parameter calculation unit 17 calculates the road width w based on the road position and road width indicated by the structure information included in the read map data.

[0056] In addition, the transmission power P T , transmitting antenna gain G T , base station feeder loss L f , receiving antenna gain G R , frequency f, and wavelength λ are input in step S1 or step S2. The distance d between the base station and the received power evaluation point is calculated, for example, by the received power calculation unit 19 using the installation location of the base station obtained from the base station information and the position of the received power evaluation point obtained from the topographical information (latitude, longitude, and altitude) included in the map data. The road angle φ is calculated, for example, by the evaluation point side parameter calculation unit 17 using information on the road position and the installation location and installation method of the base station obtained from the base station information. The road position information is obtained from structure information included in the map data of the area corresponding to the evaluation point side parameter evaluation mesh. The height h2 of the received power evaluation point is obtained, for example, by the received power calculation unit 19 from the topographical information included in the map data.

[0057] According to this embodiment, the received power estimation device 1 creates a base station side parameter evaluation mesh and / or an evaluation point side parameter evaluation mesh separately from the received power evaluation mesh. This makes it possible to create a mesh of an appropriate size for deriving the values ​​of parameters used in radio wave propagation calculations, regardless of the size of the received power evaluation mesh.

[0058] Furthermore, radio wave propagation is subject to short-term fluctuations, which occur due to obstructions such as buildings as mobile terminals move between transmitter and receiver. For example, when applying the channel model of ITU-R M.2135, the distance between two points at which the autocorrelation coefficient of short-term fluctuations is 0.5 is 50 m. From this, for example, the evaluation point side parameter evaluation mesh creation unit 154 can create an evaluation point side parameter evaluation mesh with a side length of 100 m by taking 50 m each in the east, west, north, and south directions from the center of the mesh created to derive the values ​​of the evaluation point side parameters.

[0059] In the above description, the received power evaluation mesh, the base station side parameter evaluation mesh, and the evaluation point side parameter evaluation mesh are rectangular, but they may be other than rectangular.

[0060] According to the above-described embodiment, the mesh size for calculating the received power and the mesh size for calculating the value of the radio wave propagation calculation parameter can be set independently, so that it is possible to calculate the received power of radio waves at each received power evaluation point with high accuracy regardless of the mesh size for calculating the received power.

[0061] The received power estimation device 1 may be realized by a plurality of computer devices connected to a network. In this case, it is possible to arbitrarily determine which of the plurality of computer devices each functional unit of the received power estimation device 1 is realized by. For example, the map DB 14 and the other functional units may be realized by different computer devices. Furthermore, the same functional unit may be realized by a plurality of computer devices.

[0062] 7 is a diagram showing an example of the hardware configuration of the received power estimation device 1. The received power estimation device 1 includes a processor 71, a storage unit 72, a communication interface 73, and a user interface 74.

[0063] The processor 71 is a central processing unit that performs calculations and control. The processor 71 is, for example, a CPU (central processing unit) or a GPU (Graphics Processing Unit). The processor 71 reads and executes programs from the storage unit 72. The storage unit 72 further has a work area when the processor 71 executes various programs. The communication interface 73 is connected to other devices so as to be able to communicate with them. The user interface 74 is an input device such as a keyboard, a pointing device (a mouse, a tablet, etc.), a button, a touch panel, etc., and a display device such as a display. Human operations are input via the user interface 74.

[0064] At least some of the functions of the received power estimation device 1 described above are realized by the processor 71 reading and executing a program from the storage unit 72. The program of the received power estimation device 1 may be recorded on a computer-readable recording medium. Examples of the computer-readable recording medium include portable media such as flexible disks, optical magnetic disks, ROMs, and CD-ROMs, and storage devices such as hard disks built into computer systems. The program of the received power estimation device 1 may be transmitted via a telecommunications line. Note that at least some of the functions of the received power estimation device 1 may be realized using hardware such as an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA). The map data DB2 may be realized using the storage unit 72. The radio system information input unit 11, the base station information input unit 12, and the evaluation range designation unit 13 may be realized using a user interface 74.

[0065] According to the embodiment described above, the received power estimation device includes an evaluation range division unit, a matching data generation unit, and a received power calculation unit. The evaluation range division unit performs a process of dividing the evaluation range, which is a geographical range in which the received power is evaluated, into received power evaluation meshes for calculating the received power at evaluation points located within the evaluation range, and a process of creating a parameter evaluation mesh within the evaluation range for obtaining values ​​of radio wave propagation calculation parameters used in calculating the received power at the evaluation points. The matching data generation unit generates data indicating the correspondence between the received power evaluation meshes and the parameter evaluation meshes. The matching data generation unit corresponds, for example, to the matching list generation unit 18 in the embodiments. The received power calculation unit calculates the received power at the evaluation point by radio wave propagation calculation using values ​​of radio wave propagation calculation parameters obtained based on information about the topography or features included in the parameter evaluation mesh corresponding to the received power evaluation mesh to which the evaluation point belongs.

[0066] The size of the parameter evaluation mesh may be determined by setting a threshold value for the autocorrelation coefficient of fluctuations in radio wave propagation according to the frequency of the radio wave received at the evaluation point or according to the radio wave propagation calculation model used for the radio wave propagation calculation. For example, the size of the parameter evaluation mesh may be determined according to the frequency of the radio wave received at the evaluation point or according to the radio wave propagation calculation model used for the radio wave propagation calculation so that the autocorrelation coefficient of fluctuations in radio wave propagation is equal to or greater than a threshold value.

[0067] The evaluation range dividing unit may select a radio wave propagation calculation model to be used for radio wave propagation calculation in accordance with the distance between the evaluation point and a wireless device that radiates radio waves to the evaluation point.

[0068] The evaluation range dividing unit may perform a process of dividing the evaluation range into first parameter evaluation meshes for calculating values ​​of first radio wave propagation calculation parameters using information on terrain or features around the evaluation point, and a process of creating second parameter evaluation meshes around installation positions of wireless devices in the evaluation range for calculating values ​​of second radio wave propagation calculation parameters using information on terrain or features around the wireless devices that radiate radio waves to the evaluation point. The matching data generating unit may generate data indicating correspondence relationships between the received power evaluation meshes, the first parameter evaluation meshes, and the second parameter evaluation meshes. The received power calculation unit calculates received power at the evaluation point by radio wave propagation calculation using values ​​of the first radio wave propagation calculation parameters calculated based on information on terrain or features included in the first parameter evaluation mesh corresponding to the received power evaluation mesh to which the evaluation point belongs, and values ​​of the second radio wave propagation calculation parameters calculated based on information on terrain or features included in the second parameter evaluation mesh corresponding to the received power evaluation mesh to which the evaluation point belongs.

[0069] Although the embodiments of the present invention have been described in detail above with reference to the drawings, the specific configurations are not limited to these embodiments, and include designs within the scope of the gist of the present invention. [Explanation of symbols]

[0070] 1. Received power estimation device 11. Radio system information input section 12 Base station information input section 13 Evaluation range specification section 14 Map DB 15 Evaluation range division section 17 Evaluation point side parameter calculation unit 18 Matching list generation unit 19 Received power calculation section 20 Evaluation result output section 71 processors 72 Memory section 73 Communication Interface 74 User Interface 151 Mesh creation unit for receiving power evaluation 152 Radio wave propagation calculation model selection section 153 Base station parameter evaluation mesh creation unit 154 Evaluation point side parameter evaluation mesh creation unit

Claims

1. an evaluation range division unit that performs a process of dividing an evaluation range, which is a geographical range in which received power is evaluated, into received power evaluation meshes for calculating received power at evaluation points located within the evaluation range, and a process of creating a parameter evaluation mesh in the evaluation range, with the same size as or a different size from the received power evaluation mesh, for obtaining values ​​of radio wave propagation calculation parameters used in calculating received power at the evaluation points; a matching data generating unit that generates data indicating a correspondence relationship between the received power evaluation mesh and the parameter evaluation mesh; a received power calculation unit that calculates the received power at the evaluation point by radio wave propagation calculation using the values ​​of the radio wave propagation calculation parameters obtained based on information on the topography or features included in the parameter evaluation mesh corresponding to the received power evaluation mesh to which the evaluation point belongs; A received power estimation device comprising:

2. An evaluation range division unit that performs the process of dividing an evaluation range, which is a geographical range in which received power is evaluated, into a received power evaluation mesh for calculating received power at evaluation points located within said evaluation range, and the process of creating a parameter evaluation mesh in said evaluation range for obtaining values ​​of radio wave propagation calculation parameters used to calculate received power at said evaluation points; a matching data generating unit that generates data indicating a correspondence relationship between the received power evaluation mesh and the parameter evaluation mesh; a received power calculation unit that calculates the received power at the evaluation point by radio wave propagation calculation using the values ​​of the radio wave propagation calculation parameters obtained based on information on the topography or features included in the parameter evaluation mesh corresponding to the received power evaluation mesh to which the evaluation point belongs; Equipped with The size of the parameter evaluation mesh is determined by determining a threshold value of an autocorrelation coefficient of fluctuations in radio wave propagation according to the frequency of the radio wave received at the evaluation point or according to the radio wave propagation calculation model used for the radio wave propagation calculation. Received power estimation device.

3. An evaluation range division unit that performs the process of dividing an evaluation range, which is a geographical range in which received power is evaluated, into a received power evaluation mesh for calculating received power at evaluation points located within said evaluation range, and the process of creating a parameter evaluation mesh in said evaluation range for obtaining values ​​of radio wave propagation calculation parameters used to calculate received power at said evaluation points; a matching data generating unit that generates data indicating a correspondence relationship between the received power evaluation mesh and the parameter evaluation mesh; a received power calculation unit that calculates the received power at the evaluation point by radio wave propagation calculation using the values ​​of the radio wave propagation calculation parameters obtained based on information on the topography or features included in the parameter evaluation mesh corresponding to the received power evaluation mesh to which the evaluation point belongs; Equipped with the evaluation range division unit selects a radio wave propagation calculation model to be used for the radio wave propagation calculation in accordance with a distance between the evaluation point and a wireless device that radiates radio waves to the evaluation point. Received power estimation device.

4. An evaluation range division unit that performs the process of dividing an evaluation range, which is a geographical range in which received power is evaluated, into a received power evaluation mesh for calculating received power at evaluation points located within said evaluation range, and the process of creating a parameter evaluation mesh in said evaluation range for obtaining values ​​of radio wave propagation calculation parameters used to calculate received power at said evaluation points; a matching data generating unit that generates data indicating a correspondence relationship between the received power evaluation mesh and the parameter evaluation mesh; a received power calculation unit that calculates the received power at the evaluation point by radio wave propagation calculation using the values ​​of the radio wave propagation calculation parameters obtained based on information on the topography or features included in the parameter evaluation mesh corresponding to the received power evaluation mesh to which the evaluation point belongs; Equipped with the evaluation range division unit performs a process of dividing the evaluation range into a first parameter evaluation mesh for calculating a value of a first radio wave propagation calculation parameter using information on topography or features around the evaluation point, and a process of creating a second parameter evaluation mesh for calculating a value of a second radio wave propagation calculation parameter using information on topography or features around a wireless device that radiates radio waves to the evaluation point, around an installation position of the wireless device in the evaluation range, the matching data generation unit creates data indicating a correspondence relationship between the received power evaluation mesh, the first parameter evaluation mesh, and the second parameter evaluation mesh, the received power calculation unit calculates the received power at the evaluation point by radio wave propagation calculation using a value of the first radio wave propagation calculation parameter calculated based on information on topography or features included in the first parameter evaluation mesh corresponding to the received power evaluation mesh to which the evaluation point belongs, and a value of the second radio wave propagation calculation parameter calculated based on information on topography or features included in the second parameter evaluation mesh corresponding to the received power evaluation mesh to which the evaluation point belongs. Received power estimation device.

5. a mesh division step of dividing an evaluation range, which is a geographical range in which the received power is evaluated, into meshes for evaluating received power for calculating the received power at evaluation points located within the evaluation range; a mesh creation step of creating a parameter evaluation mesh in the evaluation range, the mesh having the same size as or a different size from the reception power evaluation mesh, for obtaining values ​​of radio wave propagation calculation parameters used in calculating the reception power at the evaluation point; a matching data generating step of generating data indicating a correspondence relationship between the received power evaluation mesh and the parameter evaluation mesh; a received power calculation step of calculating the received power at the evaluation point by radio wave propagation calculation using the values ​​of the radio wave propagation calculation parameters obtained based on information on topography or features included in the parameter evaluation mesh corresponding to the received power evaluation mesh to which the evaluation point belongs; A received power estimation method comprising:

6. Computer, A program for causing the received power estimation device according to any one of claims 1 to 4 to function.

Images